UNITED NATIONS, United States (REUTERS) - China on Tuesday (May 23) pushed for dialogue with North Korea and the full implementation of United Nations sanctions on Pyongyang over its ballistic missile and nuclear tests, skirting questions about Beijing's talks with the United States on possible new measures.

Almost a month ago Washington began discussions with North Korea ally China on strengthening UN sanctions on Pyongyang following repeated missile tests. However, a week ago US Ambassador Nikki Haley said Beijing had gone quiet.

Traditionally, the United States and China have negotiated new sanctions before involving the remaining 13 UN Security Council members. The Trump administration has been aggressively pressing China to rein in North Korea, warning that all options are on the table if Pyongyang persists with its nuclear and missile development.

When asked on Tuesday if Beijing was talking to Washington about possible new sanctions, China's UN Ambassador Liu Jieyi said: "It's up to the council to decide what we should do in the current situation. We're working closely with other members."

Liu spoke after a closed-door Security Council meeting on North Korea's latest missile test on Sunday. Pyongyang said it launched an intermediate-range ballistic missile which met all technical requirements and could now be mass-produced, although US officials questioned the extent of its progress.

The Security Council first imposed sanctions on Pyongyang in 2006 and ratcheted up the measures in response to five nuclear tests and two long-range missile launches. North Korea is threatening a sixth nuclear test.

"First and foremost, it is important to implement the Security Council resolutions in a comprehensive way," Liu said. "We should also work to reduce tension, to de-escalate, and also to try to achieve denuclearisation through dialogue."

Britain's UN Ambassador Matthew Rycroft and French UN Ambassador Francois Delattre both said on Tuesday they supported strengthening the UN sanctions on North Korea.

North Korea, also known as the Democratic People's Republic of Korea (DPRK), has vowed to develop a missile mounted with a nuclear warhead that can strike the mainland United States, saying the programme is necessary to counter US aggression.

"We don't see why dialogue cannot take place in the current situation now," Liu said. "It takes political will."

US President Donald Trump said on May 1 he would be"honoured" to meet the North's leader, Kim Jong Un, under the right conditions. A US State Department spokesman has said the country would have to "cease all its illegal activities and aggressive behaviour in the region."